<?php // $Id$

//  Displays a post, and all the posts below it.
//  If no post is given, displays all posts in a discussion

	require_once('../../config.php');

	$d	  = required_param('d', PARAM_INT);				// Discussion ID
	$parent = optional_param('parent', 0, PARAM_INT);		// If set, then display this post and all children.
	$mode   = optional_param('mode', 0, PARAM_INT);		  // If set, changes the layout of the thread
	$move   = optional_param('move', 0, PARAM_INT);		  // If set, moves this discussion to another forum
	$mark   = optional_param('mark', '', PARAM_ALPHA);	   // Used for tracking read posts if user initiated.
	$postid = optional_param('postid', 0, PARAM_INT);		// Used for tracking read posts if user initiated.

	if (!$discussion = get_record('forum_discussions', 'id', $d)) {
		error("Discussion ID was incorrect or no longer exists");
	}

	if (!$course = get_record('course', 'id', $discussion->course)) {
		error("Course ID is incorrect - discussion is faulty");
	}

	if (!$forum = get_record('forum', 'id', $discussion->forum)) {
		notify("Bad forum ID stored in this discussion");
	}

	if (!$cm = get_coursemodule_from_instance('forum', $forum->id, $course->id)) {
		error('Course Module ID was incorrect');
	}

	require_course_login($course, true, $cm);

/// Add ajax-related libs
	require_js(array('yui_yahoo', 'yui_event', 'yui_dom', 'yui_connection', 'yui_json'));
	require_js($CFG->wwwroot . '/mod/forum/rate_ajax.js');

	// move this down fix for MDL-6926
	require_once('lib.php');

	$modcontext = get_context_instance(CONTEXT_MODULE, $cm->id);
	require_capability('mod/forum:viewdiscussion', $modcontext, NULL, true, 'noviewdiscussionspermission', 'forum');

	if ($forum->type == 'news') {
		if (!($USER->id == $discussion->userid || (($discussion->timestart == 0
			|| $discussion->timestart <= time())
			&& ($discussion->timeend == 0 || $discussion->timeend > time())))) {
			error('Discussion ID was incorrect or no longer exists', "$CFG->wwwroot/mod/forum/view.php?f=$forum->id");
		}
	}

/// move discussion if requested
	if ($move > 0 and confirm_sesskey()) {
		$return = $CFG->wwwroot.'/mod/forum/discuss.php?d='.$discussion->id;

		require_capability('mod/forum:movediscussions', $modcontext);

		if ($forum->type == 'single') {
			error('Cannot move discussion from a simple single discussion forum', $return);
		}

		if (!$forumto = get_record('forum', 'id', $move)) {
			error('You can\'t move to that forum - it doesn\'t exist!', $return);
		}

		if (!$cmto = get_coursemodule_from_instance('forum', $forumto->id, $course->id)) {
			error('Target forum not found in this course.', $return);
		}

		if (!coursemodule_visible_for_user($cmto)) {
			error('Forum not visible', $return);
		}

		require_capability('mod/forum:startdiscussion',
			get_context_instance(CONTEXT_MODULE,$cmto->id));

		if (!forum_move_attachments($discussion, $forumto->id)) {
			notify("Errors occurred while moving attachment directories - check your file permissions");
		}
		set_field('forum_discussions', 'forum', $forumto->id, 'id', $discussion->id);
		set_field('forum_read', 'forumid', $forumto->id, 'discussionid', $discussion->id);
		add_to_log($course->id, 'forum', 'move discussion', "discuss.php?d=$discussion->id", $discussion->id, $cmto->id);

		require_once($CFG->libdir.'/rsslib.php');
		require_once('rsslib.php');

		// Delete the RSS files for the 2 forums because we want to force
		// the regeneration of the feeds since the discussions have been
		// moved.
		if (!forum_rss_delete_file($forum) || !forum_rss_delete_file($forumto)) {
			error('Could not purge the cached RSS feeds for the source and/or'.
				   'destination forum(s) - check your file permissionsforums', $return);
		}

		redirect($return.'&amp;moved=-1&amp;sesskey='.sesskey());
	}

	$logparameters = "d=$discussion->id";
	if ($parent) {
		$logparameters .= "&amp;parent=$parent";
	}

	add_to_log($course->id, 'forum', 'view discussion', "discuss.php?$logparameters", $discussion->id, $cm->id);

	unset($SESSION->fromdiscussion);

	if ($mode) {
		set_user_preference('forum_displaymode', $mode);
	}

	$displaymode = get_user_preferences('forum_displaymode', $CFG->forum_displaymode);

	if ($parent) {
		// If flat AND parent, then force nested display this time
		if ($displaymode == FORUM_MODE_FLATOLDEST or $displaymode == FORUM_MODE_FLATNEWEST) {
			$displaymode = FORUM_MODE_NESTED;
		}
	} else {
		$parent = $discussion->firstpost;
	}

	if (! $post = forum_get_post_full($parent)) {
		error("Discussion no longer exists", "$CFG->wwwroot/mod/forum/view.php?f=$forum->id");
	}


	if (!forum_user_can_view_post($post, $course, $cm, $forum, $discussion)) {
		error('You do not have permissions to view this post', "$CFG->wwwroot/mod/forum/view.php?id=$forum->id");
	}

	if ($mark == 'read' or $mark == 'unread') {
		if ($CFG->forum_usermarksread && forum_tp_can_track_forums($forum) && forum_tp_is_tracked($forum)) {
			if ($mark == 'read') {
				forum_tp_add_read_record($USER->id, $postid);
			} else {
				// unread
				forum_tp_delete_read_records($USER->id, $postid);
			}
		}
	}

	$searchform = forum_search_form($course);

	$navlinks = array();
	$navlinks[] = array('name' => format_string($discussion->name), 'link' => "discuss.php?d=$discussion->id", 'type' => 'title');
	if ($parent != $discussion->firstpost) {
		$navlinks[] = array('name' => format_string($post->subject), 'type' => 'title');
	}

	$navigation = build_navigation($navlinks, $cm);
	print_header("$course->shortname: ".format_string($discussion->name), $course->fullname,
					 $navigation, "", "", true, $searchform, navmenu($course, $cm));


/// Check to see if groups are being used in this forum
/// If so, make sure the current person is allowed to see this discussion
/// Also, if we know they should be able to reply, then explicitly set $canreply for performance reasons

	if (isguestuser() or !isloggedin() or has_capability('moodle/legacy:guest', $modcontext, NULL, false)) {
		// allow guests and not-logged-in to see the link - they are prompted to log in after clicking the link
		$canreply = ($forum->type != 'news'); // no reply in news forums

	} else {
		$canreply = forum_user_can_post($forum, $discussion, $USER, $cm, $course, $modcontext);
	}

/// Print the controls across the top

	echo '<table width="100%" class="discussioncontrols"><tr><td>';

	// groups selector not needed here

	echo "</td><td>";
	forum_print_mode_form($discussion->id, $displaymode);
	echo "</td><td>";

	if ($forum->type != 'single'
				&& has_capability('mod/forum:movediscussions', $modcontext)) {

		// Popup menu to move discussions to other forums. The discussion in a
		// single discussion forum can't be moved.
		$modinfo = get_fast_modinfo($course);
		if (isset($modinfo->instances['forum'])) {
			if ($course->format == 'weeks') {
				$strsection = get_string("week");
			} else {
				$strsection = get_string("topic");
			}
			$section = -1;
			$forummenu = array();
			foreach ($modinfo->instances['forum'] as $forumcm) {
				if (!$forumcm->uservisible || !has_capability('mod/forum:startdiscussion',
					get_context_instance(CONTEXT_MODULE,$forumcm->id))) {
					continue;
				}

				if (!empty($forumcm->sectionnum) and $section != $forumcm->sectionnum) {
					$forummenu[] = "-------------- $strsection $forumcm->sectionnum --------------";
				}
				$section = $forumcm->sectionnum;
				if ($forumcm->instance != $forum->id) {
					$url = "discuss.php?d=$discussion->id&amp;move=$forumcm->instance&amp;sesskey=".sesskey();
					$forummenu[$url] = format_string($forumcm->name);
				}
			}
			if (!empty($forummenu)) {
				echo "<div style=\"float:right;\">";
				echo popup_form("$CFG->wwwroot/mod/forum/", $forummenu, "forummenu", "",
								 get_string("movethisdiscussionto", "forum"), "", "", true,'self','',NULL,
								 get_string('move'));
				echo "</div>";
			}
		}
	}
	echo "</td></tr></table>";

	if (!empty($forum->blockafter) && !empty($forum->blockperiod)) {
		$a = new object();
		$a->blockafter  = $forum->blockafter;
		$a->blockperiod = get_string('secondstotime'.$forum->blockperiod);
		notify(get_string('thisforumisthrottled','forum',$a));
	}

	if ($forum->type == 'qanda' && !has_capability('mod/forum:viewqandawithoutposting', $modcontext) &&
				!forum_user_has_posted($forum->id,$discussion->id,$USER->id)) {
		notify(get_string('qandanotify','forum'));
	}

	if ($move == -1 and confirm_sesskey()) {
		notify(get_string('discussionmoved', 'forum', format_string($forum->name,true)));
	}

	$canrate = has_capability('mod/forum:rate', $modcontext);
	forum_print_discussion($course, $cm, $forum, $discussion, $post, $displaymode, $canreply, $canrate);

	print_footer($course);


?>
